Process and apparatus for polishing grain



J. A. SMITH.

PROCESS AND APPARATUS FOR POLISHING GRAIN.

APPLICATION FILED NOV. 11, I919.

Patented Aug. 30, 1921.

2 SHEETS-SHEET I- ATTORNEY J. A. SMITH. I PROCESS AND APPARATUS FOR POLISHING GRAIN. APPLICATION FILED NOV- H, 1919.

1,389,277. Patented Aug. 30,1921.

2SHEETS-SHEET 2.

'INVEPAT? ATTORNEY UNITED STATES JOSEPH A. SMITH, OF DE WITT, ARKANSAS.

rnocnss AND APPARATUS FOR POLISHING GRAIN. i

Application filed November 11, 1919.

T 0 all whom it may concern:

Be it known that I, Josnrrr A. SMITH, a citizen of theUnited States, residing at De Witt, in the county of Arkansas and State of Arkansas, have invented certain new and useful Improvements in Processes and Apparatus for Polishing Grain, of which the following is a full, clear, and exact description, such as will enable others skilled in the art to which it appertains to make and use the same.

This invention relates to the art of milling grain, such as rice, and with respect to its more specific features to processes and apparatus for polishing such grain.

One of the objects of the invention is the provision of a practical process and appa ratus of the character referred to wherewith breakage of the grain is avoided and the grain is efliciently cleaned and polished.

Other objects will be in part obvious and in part pointed out hereinafter.

The invention accordingly consists in the features of construction, combinations of elements and arrangement of parts which will be exemplified in the constructionhereinafter described and the scope of the application of which will be indicated in the following claims.

In the accompanying drawings forming part of this specification, wherein similar reference characters refer to similar parts throughout the several views,-

Figure 1 is a vertical central section of a machine embodying the invention;

Fig. 2 is a top view of the housing'of Fig. 1;

Fig. 3 is a transverse section through Fig.

1, showing the top of the rotary drum;

Fig. 4 is a detail of the rotary drum; and

Fig. 5 is a section through the wall of the rotary drum; and

Fig. 6 is an enlarged cross section of the polishing brush Wall.

Referring now more specifically to the drawings, there is provided a housing com.- posed of an upright cylindrical wall 1, in the present instance rectangular in shape, and upper and lower end walls or heads 2 and 3, these latter being castings bolted in position as illustrated. Journaled in the housing is an upright rotary shaft 4 which may have a step bearing in a base casting 5 below the end casting 3, said shaft having a belt pulley 6 Specification of Letters Patent.

Serial No. 337,284.

disposed between the castings 3 and 5. Power may be applied to the pulley 6 by means of a belt as will be understood.

WYithin the housing 1 is located the grain polishing brush which, in the present embodiment, is in the form of a cylindrical rotary polishing drum laterally spaced from the housing wall 1 and preferably concentrio with such wall. This drum is composed of a cylindrical wall 7 and upper and lower end walls 8 and 9, the wall 7 being made up of wood staves rabbeted to the ends 8 and 9 and forming a solid cylindrical drum wall except as will hereinafter appear. The end drum walls 8 and 9 may be of cast metal in the shape of spiders as indicated in plan in Fig. 3, such spiders being suitably attached to the shaft 4. for rotation with the latter. In the case of a long drum, an intermediate spider 10 may be employedto brace the-drum intermediate its ends.

casing is cooperatively associated withv the polishing drum 7 to form a passageway for the grain to be polished. In the present embodiment the casing includes a foraminous wall 11 concentric with the drum 7 and laterally spaced from the housing wall 1. As illustrated, the foraminous wall 11 is located quite close to the drum wall 7 and may be composed of Wire mesh of such size as to permit air, particles of chaff, polish, etc, to pass therethrough without permitting the passage of the grain being polished, in the present embodiment, rice grains. 7 The wire mesh may be mounted at its upper and lower ends in frame pieces 12 and 13 secured to the housing heads 2 and 3 respectively. In each of the housing heads 2 and 3 are ports for the admission of air from the exterior of the housing, such air being designed to enter the interior of the polishing drum and thence to pass through the grain passageway. The air inlet ports for the head 2 are indicated at 14 opposite the spider 8, and both the head 2 and the spider 8 are provided with cylindrical flanges or baffles 15 and 16 which confine the entering air and direct it into the interior of the polishing drum, while permitting rotation of the drum head 8 relative to the housing head 2. Above the polishing drum and radially outside of the air ports 14 the housing head 2 is provided with grain inlets, being openings 17 disposed substantially in alinement with Patented Aug. 30, 1921.

the grain passageway 18 between the drum and easing, so that grain flowing into the opening 17 will readily enter such grain passageway and flow down toward the lower end of the polishing drum. The numerals 19 indicate the air inlet ports for the lower end of the housing, being openings in the housing head 3, tubes 20 being disposed in these openings and extending toward the lower drum spider 9 so as to conduct air across the space between the housing head 8 and the lower end of the polishing drum. These tubes 20 are carried by the head 3 and terminate adjacent the spider 9, their inner ends discharging through the openings be tween the arms of spider 9.

The air entering the interior of the polishing drum through the openings 1a and 19 is designed to pass across the grain passageway 18, thereby coming in contact with the mass of grain being polished, and to this end the polishing brush, in the present instance the drum 7, is provided with air openings 21 to admit air to its polishing face from the interior of the drum. In the present embodiment it will be observed that the staves going to make up the polishing drum are provided with two relatively narrow air openings tak ing up the greater extent of the longitudinal dimension of the drum. In this wise, air in the interior of the drum maybe made to enter the grain passageway 18 at many different points around the drum. The outer surface of the polishing drum is covered with wool and pad-skin cushions which as well overlie the air openings 21. These cushions, one for each stave, are fastened to the drum at their advance edges, as the drum rotates, and the centrifugal force consequent on rotation of the drum causes the cushions to turn on their advance edges, so that they lift and permit the air to pass between their rear edges and the advance edge of the ad jacent cushion. It will also be noted that the currents of air passing through the openings 21 behind the pads tend to cause the latter to separate from the surface of the drum 7 acting as a cushion for said pads.

That portion of the housing immediately surrounding the polishing brush and the foraminous casing provides an air chamber overlying the full length of the grain passageway 18, so that the air passing through the grain passageway and the casing 11 from the interior of the drum discharges into this air chamber together with chaff, polish, etc., entrained therewith. The numerals 30 indicate air exit ports for this chamber, and 31 indicates a rotary exhaust fan adapted to be operated to draw air from said chamber and eject it into the atmosphere, or to a device for collecting the chaff, dust, flour, etc., which may be discharged therewith. Any suitable means may be employed for driving the fan 31,

The operation may be briefly explained as follows:

The polishing brush 7 and fan 31 are set in operation, a speed of, say, 300 R. P. M. being developed in the polishing brush, relative rotary motion between the brush and casing being thus attained. The rice is then delivered through the inlet ports 17 and fines downwardly in the grain passageway 18, being polished and freed from floury matter, fine particles of rice powder, bran, etc., which may have contaminated the rice prior to the polishing operation. The fan 31 will establish currents of air from the outside of the housing through the ports 19 and 1 1 to the interior of the drum, thence through the polishing face of the brush, or drum, via the openings 21. These currents pass across the grain passageway 18 and thence through the air openings in the casing 11, thence into the air chamber or housing, and finally through the ports 30 to the fan, whence they are ejected. It will be observed that the air inlet ports 1% admit air to one side of the grain passageway 18, whereas the ports 30 in the housing communicate with the other side of such grain passageway so that the air, or the great bulk of it, is forced to pass across the grain passageway. Short circuiting of the air currents around the ends of the drum is substantially avoided by the baflies 15 and 16 at one end and the arrangement of the air tubes 20 at the other end. in this wise the entry ports 14 and the air exit ports 30 are substantially sealed from communication with each other except across the grain passageway 18, so that upon operation of the fan the air currents will be established in the predetermined direction through and transversely of the direction of flow of the grain being polished. One of the efiects of the air is to cool the grain simultaneously with its polishing and thus avoid breakage of the grain due to possible rise of temperature otherwise engendered in the polishing operation. Also it is to be noted that the air currents will strip floury matter, particles of polish, chaff, etc., from the rice grains and convey them away, so that the rice will be discharged in a clean condition, polished and ready for the market.

The housing is substantially air tight, and the draft of the fan is confined more especially to within the length of the polishing drum so that there may be as little tendency as possible to draw air from outside the area of the polishing drum. To this end the upper end of the casing 11 terminates adjacent the upper end of the drum. The lower end of the casing also terminates adjacent the lower end of the drum, the polished or brushed rice being discharged at this point and flowing downwardly through discharge openings 32 in the lower head 3 of the housing, whence it may be directed to any convenient point. To guide the polished grain to the openings 82, an inwardly inclined outer wall 34 and an inner conical wall 35 may be provided. I The tubes 20 may extend through the wall 35.

It is to be noted. that some small particles of rice may pass through the wire mesh -11, with the polish, and that this fine rice will drop to the head 3 and emergethrough the spouts or conduits 33 onto a conveyer 34' which will conduct it to a point apart from that discharged through the openings 32. In this way the fine rice is separated from the polish and collected in the outer chamber as an auxiliary rice product, brewers rice, in clean condition. y n

Thus by the above described construction are accomplished, among others, the objects hereinbefore referred to.

i As many changes could be made in the above construction and many apparently widely difierent embodiments of this invention could bemade without departing from the scope thereof, it is intended that all matter contained in the above description or shown in the accompanying drawings shall be interpreted as illustrative and no in a limiting sense. i I

It is also to be understood that the language used in the following claims is intended to cover all of the generic and specific features of the invention herein described and all statements of the scope of the invention which, as a matter of language, might be said to fall therebetween.

Having described my invention, what I claim as new'and desire to secure by Letters Patent, is a r 1. A grain polishing machine including, in combination, a foraminous casing, a brush spaced from said casing forming a grain passage-waytherewith, means for establishingcurrentsof air through the ends of said brush and across said passage-way, a housing for said casing, and an exhaust port formed in a wall of said housing.

2. A in combination, a foraminous casing, a brush spaced from said casing forming a grain passageway therewith, means for establishing currents of air through the ends of said brush and across said passage-way, and air baffles at the ends of said brush.

3. A grain polishing machine including, in combination, a foraminous casing, a brush spaced from said casing forming a grain passage-way therewith, means for establishing currents of air through the ends of said brush and across said passage-way, and means for directing the air currents through the ends of said brush.

4. A grain polishing machine including, in combination, a foraminous casing, a brush spaced from said casing forming a grain passage-way therewith, a housing for said grain polishing machine including,

casing, air admission ports in said housing communicating with the extremities of said brush, means for establishing air currents through said ports and across said passageway, an air exhaust port in a wall of said housing. and means for preventing communication between said admission ports and said exhaust port except across said passage-way.

5. Ina grain polishing apparatus, in combination, a brush having spaced walls and a polishing face, a casingfor said brush spaced therefrom forming a' grain passageway, said walls being ings therein, a housing for said casing having openings communicating with the open ings in said walls, and means for establishing air currents through said openings and across said passage-way.

6. In a grain polishing apparatus, in combination, a brush having spaced walls and a polishing face, a casing for said brush spaced therefrom'forming a grain passageway, said walls being provided with openings therein, a housing for said casing having openings communicating with the openings in said walls, meansfor establishing air currents through said openings and across said passage-way, and an exhaust port in said housing for said air currents.

7 In a grain polishing apparatus, incombination, a brush having spaced walls and a polishing face, a casing for said brush spaced therefrom forming a grain passage-way, said walls being provided with openings therein, a housing for said casing having openings communicating with the openings in said walls, means for establishing air currents through said openings and across said passage-way, and a grain admission opening in said housing communicating with said passage-way.

8. In a grain polishing apparatus, in combination, a brush having spaced walls and a polishing face, a casing for said brush spaced therefrom forming a grain passage-way, said Walls being provided with' openings therein,

a housing for said casing having openings communicating with theopenings in said walls, means for establishing air currents through said openings and across said passage-way, an exhaust port in said housing for said air currents, and a grain admission opening in said housing communicating with said passage-way.

9. In a grain polishing apparatus, in combination, a brush having spaced walls and a polishing face, a casing for said brush spaced therefrom forming a grain passage-way, said walls being provided with openings therein, a housing for said casing having openings communicating with the openings in said walls, means for establishing air currents through said openings and across said passage-way, an exhaust port in said housing provided with open-' for said air current, and means for preventing the air currents from passing from said openings to said port except through said passage-way.

10. In a grain polishing apparatus, in combination, a brush having a polishing pad and means providing an air cushion for said pad.

11. In a grain polishing apparatus, in combination, a brush having a polishing pad and means for admitting air beneath said pad.

12. In a grain polishing apparatus, in combination, a brush having a polishing pad mounted at one edge and having a free edge, and means for admitting air intermediate said edges.

13. In a grain polishing apparatus, in combination, a rotary brush having a foraminous surface, polishing pads overlying said surface, and means for producing currents of air through said surface.

14. In a grain polishing apparatus, in combination, a rotary brush having a foraminous surface, polishing pads overlying said surface, means forming a grain passage-way adjacent said surface, and means for producing currents of air through said surface and across said passage-way.

15. In a grain polishing apparatus, in combination, a rotary brush having a foraminous surface, polishing pads overlying said surface, means forming a grain passageway adjacent said surface, means for producing currents of air through said surface and across said passage-way, a housing for said casing adapted to receive said air currents, and an exhaust port for said currents.

16. In a grain polishing apparatus, in combination, a brush having openings in the surface thereof, polishing padskins secured'to said brush, and means for causing air currents through said openings including a port disposed laterally within the horizontal limits of said brush.

17 In a grain polishing apparatus, in combination, a brush having openings in the surface thereof, polishing padskins secured to said brush, means for causing air currents through said openings including a port disposed laterally within the horizontal limits of said brush, and means for admitting said air currents at opposite ends of said brush.

18. In a grain polishing apparatus, in combination, a brush having openings in the surface thereof, and means for causing air currents through said openings including a port disposed laterally within the horizontal limits of said brush.

19. In a grain polishing apparatus, in combination, a brush having openings in the surface thereof, means for causing air currents through said openings including a port disposed laterally within the horizontal limits of'said brush, and means for admitting said air currents at opposite ends of said brush. I

20. In a grain polishing apparatus, in combination, a brush having openings in the surface thereof, means for causing air currents through said openings including a port disposed laterally within the horizontal limits of said brush, means for admitting said air currents at opposite ends of said brush, and means for separating the coarse grain from the fine.

21. A grain polishing machine including, in combination, a housing, a rotary polishing drum within said housing and laterally spaced therefrom, a casing concentric with said drum andlaterally spaced from said housing, said casing and drum cooperative to form a grain passageway, ports in the ends of said drum and housing for entry of air into said drum from the exterior of said housing, cooperative air baffles on said drum and housing, and an exhaust fan adapted to draw air from said housing, said drum having air openings in communication with said ports and said grain passageway, and'said casing having air openings in communication with said grain passageway and said housing.

22. A grain polishing brush including, in combination, a rotary wall, a padskin carried thereby and adapted to lift therefrom under the influence of centrifugal force, said wall having an air opening beneath said cushion.

In testimony whereof I affix my signature, in the presence of two witnesses.

JOSEPH A. SMITII Witnesses:

H. M. SnAMANs, J. W. ANDERSON. 

